Understanding Wallpaper Pattern Repeats
Wallpapers (wallcoverings) have what is called a pattern repeat — unless your wallpaper is a solid or has a simple texture. The pattern repeat is the vertical distance between where the pattern is identical again (repeats). That distance can be less than an inch or as much as the entire width of the wallpaper. There are several kinds of pattern repeats: random pattern match, straight across match, and drop match.
Understanding the nature of your wallpaper’s pattern repeat is important, because it affects the number of rolls you buy and the way you hang it.
If your project is complex and involves lots of cutting, irregular openings, or an out-of-square room, or if your wall covering has a tricky pattern or is otherwise a difficult type to hang, let an experienced salesperson estimate your needs.
Random pattern match: When the wallpaper pattern is random, you don't need to worry about matching any pattern at all. For obvious reasons, random patterns are great for beginners. No matter how you position the paper the pattern still looks good. A great example of a random pattern match is a texture, such as grasscloth, or a stripe.
As a general rule, you should flip every other strip to make sure there are not color variations to worry
Straight across match: A wallpaper with a straight across match is a one that starts over at the ceiling line. This means that the design has to match the strips on either side. These take more planning than random matches, but they are not typically complex patterns.
Drop match: Drop match patterns are the most complex pattern matches. These wallpapers require a good deal of planning because the pattern needs to be aligned both horizontally and vertically with the wallpaper on either side. Because of the dual alignment, dropped patterns require a good deal of waste in order to have enough wallpaper to make all the necessary pattern matches.
There are two different kinds of dropped patterns.
Half-drop match: Half-drop patterns repeat at the ceiling line on every other strip and the design tends to run diagonally. It requires three strips of wallpaper to repeat the vertical design. A half-drop match is a straight match that has been split in half. You'll need to lay out the room and determine which strips will go where ahead of time.
Multiple drop match: A multiple drop match is the most complex pattern match. It can take four or more strips to repeat the vertical design. A good example of this is a dense paisley pattern. The multiple drop match pattern looks great, but you may not want this to be your first attempt at wallpapering.
Try writing the number (in pencil) on the back of each strip to keep track of the order in which each should be hung. It can save you from a lot of confusion later on.
You might want to buy an extra roll or two of wallpaper, this will give you plenty of cushion. Check with the dealer — they might let you return the extra rolls if you don't need them. Having extra rolls is better than having to purchase new rolls that are not from the same dye lot.